So, I did a little math on Subaru's new 2.0...
 

Ok, this is just ASSUMING that the FT-86 employs Subaru's new FB boxer engine. From the press release, the engine is stated to be:
Max. output: 109 Kilowatts
Max. torque: 196 Newtonmetres
When converted, this equals:
146 HP
144 TQ

Now, since it is confirmed to have the D4-S technology, its a matter of if Yamaha is co-developing. The two closest examples we have of the added performance from D4-S are:
#1. Toyota's 3.0 and 3.5 GR engines.
3.5 with D4-S= 311HP maximum output (Lexus IS and GS engines)
3.5 without D4-S= 285HP maximum output (Toyota Camry and Avalon engines)
3.0 with D4-S= 252HP maximum output (2006 Lexus GS300 engine)
3.0 without D4-S= 228HP maximum output (Lexus GS300 Middle East version)
#2. Lexus' 4.6 and 5.0 UR engines.
4.6 with D4-S= 385HP maximum output (Lexus LS engine)
4.6 without D4-S= 347HP maximum output (Lexus GS460 engine)
5.0 with D4-S= 417HP maximum output (Lexus IS-F)

So, as you can see, the power differential is greater on larger displacements, with the 3.0 representing a 24 HP increase, 3.5 with 26 HP increase, and 4.6 with nearly 40 HP and when bored out a little with help from Yamaha, 70 HP.
Now, I know this is a boxer engine and I don't know if the effects are similar but IMO, I think the 2.0 base, naturally aspirated engine will be rated around 166-170HP and 165 TQ. If Yamaha joins in, about 185- 190 HP and 175-180 TQ.
Thoughts? Corrections?

nice work!! Lets hope Yamaha get involved!!! cause i want to see about 200hp or more!!!

Though you are somewhat correct on the gains that D4-S provides, It's not as simple as that.

You are also assuming that Direct injection will be the only modification Toyota makes to the head.

interesting work here :)
you can see that the increase is always 10% which means that the 200 target isnt hard to reach at all :)

p.s. the 3.0 uses D4, not D4-S, IIRC.

FYI people new reading this thread....Direct injection (D4) and Direct 4 injection (D4-S) are two completely different systems.

You are correct sir. My apologies

I'd rather compare this to engines of it's own size, the best example would be that in '97 Toyota got 94 kW out of the 3S-FE and when Yamaha came in they made the BEAMS which puts out 156 kW and 220 Nm of torque. Toyota has always asked Yamaha's help with powerful NA's and I can't see any reason why not this time. Anyways, this all goes down to how much power they dare to take out of the boxer without compromising the durability of the boxer. They do have the skills to go over 200 horses but will the engine stand it? I certainly hope so. Aren't boxers supposed to be better balanced than I4's because of all the pistons moving againts each other?

I don't think the engine holding together will be any problem with only 200hp, if they were to get it to around 350hp I could see it being a problem.... Maybe. But that's a LONG way off.

My 1JZGTE has 'Yamaha' on it. It's not just the NA's.

This speculation is meh. We need more details.

Starting with the bore and stroke. Then we can speculate on potential valve size (from bore) which could be used as a rough indicator of how much flow we can get out of it, as well as if it could feasibly spin reliably to the rpm needed for such flow (from stroke).

Then compression, then what valve timing system (lift?) they are using etc...

If the head is a complete re-work by Yamaha, the current info is completely irrelevant. Heads can change the motor into something completely different. Look what Lotus did to the old Chevy small block in the Corvette when they took the 250 hp L98 OHV small block 350 and turned it into the 375 hp LT5 32v DOHC small block 350. Both engines were from 1990.

(ok so the block was different too but all that power was principally from the heads...)

like i've said many times, i'll be sorely disappointed if this car has under 200hp with a 2.0L. if they can't keep the same hp/L as they did TEN YEARS AGO with the Celica GTS (180bhp from a 1.8L), then i will know they're not serious about making fun cars any longer, not including lexus cars.

wasn`t the last Celica GTS had a 2.2L 5S-FE? Or are you talking about SS-II w 2ZZ engine?

Nevermind... In US SS-II was called GT-S. My bad

Remember that was under the old rating scheme. Doesn't it make like 167hp under the new one?

Still, that motor goes 8500RPM stock. I would be happy if they just gave me that one again.

Let's not forget Subaru has an N/A EJ20 with AVCS putting out 190PS, around 187 hp in the JDM Legacy 2.0R from 2003-2009 I believe it is? Please correct me if I'm wrong. I would figure this motor would be able to produce at least as much power. Hoping for valvematic and guessing it will be between 10.0 and 11.5:1 for compression ratio which should allow 87 octane (US measurement, not sure what the rating is everywhere else) with the direct injection they are supposed to be putting in. Possibly even making it to 12.0 or 13.0 with high octane?

Well, the stock FB20 is: 1995cc, 84mm bore x 90mm stroke, 10.5:1 Compression Ratio. I don't know if that helps.

Yeah, so I made this graph the other day for the "Interesting" thread. Shows what torque/RPM combination(s) will produce 200 hp.

http://img199.imageshack.us/img199/1...00hp3mediu.jpg

My guess will be 150 ft-lbs of torque at 7000 RPM (again, only applicable for 200 hp). Of course, it may make over 200 hp so who knows. It's definitely possible.

here we go again.

:bonk: I still don't agree with that graph. No (i.c.e.) car has that torque curve. Did someone make that graph cause I'd like to know how they derived their data. It looks more like a torque curve for and electric motor than anything. I can post torque curves all day long (both real and ones I can make up) and we'll still know nothing about the engine, yet we'll continue to argue about it lol.

Edit: After looking at the graph, I assume whoever made the graph set the max power to 200hp, and calculated torque from the known rpm. If this is the case, it should have been made more clear a the beginning of the thread when it was posted. Of course even then the graph is still wrong...Power is calculated from torque and rpm ie power is dependent on torque. You have to know two before you can find the other one.

Example: The car makes 200hp. What is the rpm and torque?

Well, if the car makes 200 hp at 6000 rpm, then the torque is 175.066 ft-lbs.

If the max power is produced at 3000 rpm, then torque is 350.13 ft-lbs.

The fact of the matter is that neither torque, nor power are linear when dealing with an internal combustion engine (though there is a linear relationship between hp and torque). So again, all we're doing is guessing (and putting out false information).

holy shit you fail.

it's a graph showing how much torque at each RPM will produce 200hp. so when we "know" we WANT 200hp, we can look at the graph and see how much torque is required at a particular RPM to achieve the desired power level. it's not reasonable for any production 2.0L n/a 4 cylinder to make 350ft.lbs, but it's entirely reasonable for it to make 130ft.lbs and rev to 8000rpm.

If I asked you a question in the form of:

"Hey nate, my engine makes peak power at X RPM. I wanna hit 200HP out of this tune so I can brag to my buddies I make 200HP. How much torque should I aim for?"

It might make your life quite easy to refer to this graph.

I know algebra and maths is hard and it's for the nerds, but it is kind of a simple basic form of maths that has been used since AT LEAST 1700BC. That's almost four thousand years ago. I mean, it's like there's counting and then there's algebra and anything that's worth thinking about is kind of beyond that...

Power[hp] = (Torque [ft.lb] * RPM[w])/5252

Power*5252 = Torque*RPM

Torque = (Power*5252)/RPM

The graph simply plots Torque = (200hp*5252)/RPM

It represents more than a single car.

It represents ALL cars. ALL engines. In fact, ALL OBJECTS that can rotate and have a coupled force of 200hp.

It's a pretty big axiom.

First, way to make an ass of yourself.

Second, If we are wanting 200hp, we still don't know what torque or rpm that 200hp occurs at. In other words, we have one known, two unknowns, and one equation; which means we cannot solve the equation exactly. Read up on engines and learn some math before you post shit.




I know math can be tough, but I'm an engineer and have been teaching calculus on the side for the past four years, so I'm competent in my math skills. All your equations are correct, but the thing is that the relation ship between torque and rpm is not linear. Torque varies with rpm, increasing, then decreasing. What that graph is saying is that ass rpm's increase, torque decreases, and vice versa. However, torque does not increase as rpm decreases past a certain point.

This is incorrect for several reasons. Not all cars are the same. Not all engines have the same torque curve (in actuality, no engine has the same torque curve as another since there are slight deviations in machining and assembly-this is the reason Nissan didn't post HP numbers for their engines since it could deviate by 15hp). With spinning objects, things get more complex with mass concentrations, moments, etc.

^ I said this in the other thread, and I'll say it again:

THAT IS NOT AN ENGINE DYNO GRAPH SHOWING TORQUE OF AN ENGINE.

The graph shows what combinations of torque and rpm are required to achieve 200hp (200hp is the whole curved line), using the equation:

Power = (Torque x RPM)/5252

We know all the variables we need to know too... we know how much power we want to achieve (200hp), and then we plot points on a graph according to the rpm values going from 5000 to 9000 in this particular graph, we rearrange the equation to find the torque (using substitution for the rpm values) needed to produce 200hp at those rpm points between 5000 and 9000, and then we plot them on the graph.

Once again, THIS IS NOT AN ENGINE DYNO GRAPH.

yeah but we dont know when peak torque occurs.. what if peak torque occurs at 4000rpm? and then it stays virtually flat, only dropping a little.. untill it drops totaly around lets say 7000 rpm
you need the ACTUAL torque curve of the engine to get the power.. guessing doesnt do anyone good :p

Thank you!

We have no idea what the specs of the engine are, so why are we arguing about it? Let wait till we hear some official news and then discuss the engine.

If peak torque occurred at 4000rpm and it was virtually flat until a rev limiter of 7500rpm, then you would only need about 150ft-lbs of torque to achieve 200hp at 7000rpm (where torque begins to drop). If Toyota can manage to pull more torque out of the engine than that (which I'm sure they will), then you don't need to rev the engine as high to get to 200, and it also means (if the torque curve stays flat) you will get a higher power at a higher rpm.

As you both said, we don't know the specs of the engine, but we can hazard a guess at them... An example: The 2011 Subaru Impreza (Using this because it's a boxer engine) - produces 170ft-lbs of torque, cut another .5L off of it and it should produce about 140 ft-lbs (without D4-S). This means that you only need to keep that figure until about 7000rpm to achieve 200hp. If you increase the torque (which D4-S will do), you don't need to rev it as far to achieve that number. I think this should be easily doable for Toyota/Yamaha.

Edit: Nate89, we're arguing because it passes the time until we get more info! :D

exactly!!! hehe its fun

you seem to be determined to be obtuse, so this will likely be my last post directed to you.

That's probably for the best...:happy0180:

I'm with Snaps and NESW20 on this one. It's not a power or torque curve. Using the extremes of the graph it is showing that a motor that produces 210 lb-ft will roughly need 5000 rpm to create the target 200 hp. On the other end if it produces only 115 lb-ft it will need about 9000 rpm for 200 hp.

Edit: Some more number rambling...


Now what is a good starting point for more detail? Let's look at some of the airflow to torque and power numbers produced by some relevant engines: the IS350's V6 (for Toyota's direct/port combination injection) and Subaru's 3.0L H6 (newer FHI design, and chop off two cylinders and we get a 2.0L H4).

At its torque peak the 3.5L V6 is consuming 297.6 cfm to produce 277 lb-ft (3.5L @ 4800 rpm). This gives us 1.07 cfm/lb-ft.
At its power peak the 3.5L V6 is consuming 395.4 cfm to produce 306 hp (3.5L @ 6400 rpm). This gives us 1.292 cfh/hp.

At its torque peak the 3.0L H6 is consuming 222.6 cfm to produce 215 lb-ft (3.0L @ 4200 rpm). This gives us 1.04 cfm/lb-ft.
At its power peak the 3.0L H6 is consuming 349.5 cfm to produce 245 hp (3.0L @ 6600 rpm). This gives us 1.427 cfm/hp.

Now a hypothetical 2.0L hybrid of the 3.5L V6 and the 3.0L H6 cut down. We'll spin the motor to 6600 rpm and use the 1.292 cfm/hp figure for 233 cfm (2.0L @ 6600 rpm) and 180 hp.
Now 2.0L @ 4200 rpm and 1.07 cfm/lb-ft gives 148.3 cfm and approximately 140 lb-ft.

So based on a non-Yamaha head were looking at:
2.0L with (existing tech) direct/port injection, dual VVT-i, DOHC 16V H4:
180 hp @ 6600 rpm
140 lb-ft @ 4200 rpm

This is a reasonable output to reliability number, if not quite the magic 200 hp number that we're all looking for.

What the Yamaha head would most likely do is move the efficient range of the motor up the rev range. Say its efficiency allows it to maintain the 1.292 cfm/hp up until 7200 rpm. This gives an output of about 197 hp. And hopefully keep the low rpm air velocity (and therefore torque) up.

^ Got the cfm figures on the 4th gen 3SGSE Beams engine?

Black-Top Dual VVT-i, 11.5:1 CR version, 2.0L
207 hp @ 7600 rpm
216 Nm @ 6400 rpm (too lazy to look up how to convert to lb-ft...)

Edit for imperial: 164 lb-ft @ 6400 rpm.

207 hp @ 268.3 cfm = 1.296 cfm per hp. Teensy bit worse than the V6, but for our purposes, equal. However it is at a much higher rpm than the 3.5L V6 which is why it makes more hp to displacement.

216 Nm @ 227.2 cfm = 1.052 cfm per Nm (in imperial, somebody?)

Edit for imperial: 1.385 cfm per lb-ft This isn't great compared to the previous numbers of 1.07 or 1.04.

I'll edit this to lb-ft at a later time to better compare the torque outputs, but I'm betting the V6, thanks to the direct/port injection, is better.

Edit for imperial: So the speculation was pretty bang on. The BEAMS doesn't do too well in the torque department. The reasons for this are likely due to its lack of lift control. So at lower rpm with big lift, air intake velocity is low and combustion is impaired and it needs the higher air velocity produced from higher rpm to get good cylinder filling and combustion. Something that Valvematic could fix...:)

What we're looking for out of Toyota, Yamaha and new tech like Valvematic, is to allow us the high rpm efficiency such as from the BEAMS and keep the lower-rpm driveability of the 2GR-FSE or EZ30.

Bingo, this is exactly what we need in the FT engine.... D4-S, Valvematic, Dual-VVT-I (As Valvematic can't adjust timing)!

VVT-I is an integral part of the valvematic technology package.

p.s. @ dimman, don't remember the conversion, but the beams puts out 164ft/lbs tq.

An exciting thing about Valvematic is that if they decided to go with dual intake and exhaust runners per cylinder they could smoothly turn it from a 2 valve to a 4 valve as needed. This can create incredible cylinder filling potential and really throw out a lot more down-low torque.

Edited the BEAMS post (in blue) above.